(a) Technical Field of the Invention
The present invention generally relates to bicycle handbrakes, and more specifically to a device positioned between the handbrake operating device and the handbrake assembly of a bicycle for fast tightening and loosening the brake wire.
(b) Description of the Prior Art
Generally, on a bicycle, there are devices for fast assembly and disassembly of some parts of the bicycle. Some typical examples include the ones at the hubs of the front and rear wheels to dismount the wheels quickly. Another one is installed under the saddle and around the seat pillar so that the height of the saddle could be adjusted quickly. There are also ones for tightening and loosening the brake wires quickly.
A bicycle handbrake system usually contains a handbrake operating device installed on the handlebar of the bicycle, a handbrake assembly installed at the two sides of the rim of the front or rear wheel, and a brake wire connected between the handbrake operating device and the handbrake assembly. When a user grips an operating lever of the handbrake operating device, the brake wire is pulled so that two brake arms of the handbrake assembly are moved toward the wheel rim, and brake pads attached to the brake arms engage the wheel rim to apply a braking force. In order to achieve greater handbrake efficiency, the brake wire is tightened and the brake pads are at close proximity to the wheel rim when the handbrake is not operated. This, however, causes a problem that the wheel is unable to pass through the gap between the brake pads when the wheel is dismounted.
As such, a conventional handbrake assembly, as illustrated in FIG. 1, has its brake wire (not numbered) inside a brake cable 3 threaded through a cabling screw 2 and a locking nut 21 at an end 11 of a brake arm 110 and connected to an eccentric device 10 at an end 12 of the other brake arm 120. To dismount the wheel 4, the device 10 is operated to loosen the brake wire and the two brake arms 110 and 120 are moved away from each other. The wheel 4 then can easily pass through the gap between the brake pads 13 and 14. However, in recent years, bicycles are usually equipped with wheels having a larger tire diameter. Therefore, an ordinary rider cannot dismount the wheels conveniently and quickly even after the device 10 is operated.
Accordingly, a new and better brake wire tightening and loosening device is provided herein to obviate the foregoing shortcomings of the conventional approaches.